Abstract: Monodisperse polystyrene(PS) microcapsules containing vitamin E(VE)were prepared by membrane emulsification-dying in liquid technique. The diameter of microcapsules was about 4 times the size of the pore diameter of Shirasu porous glass (SPG) membrane, and the coefficient of variation (CV) of the microcapsule size was less than 0.2, showing a good monodispersity. Furthermore, the effects of the ratio of PS to VE (m/m) and the diameter of microcapsules on the release characteristics were investigated. When the ratio of PS to VE (m/m) is 40/1, the permeability coefficients were 0.71×10－9 and 0.74×10－9 m•s－1 corresponding to the microcapsule diameters of 21.32 and 11.45 μm, and the concentrations of VE released were 8 and 12 mg•L－1 respectively, which conform to the optimal concentration in applications.

Key words: Membrane emulsification, Drying in liquid, Vitamin E, Microcapsule, 　Controlled release